3.6 engines - why were they produced?
Discussion
It's a dangerous game trying to work out how TVR thought... 
The 3.6 gave them a more "entry level" 350bhp engine to go into the new lower-cost Tamora family replacing the Chimaera. Of course that's largely just marketing, since as you say the real world performance is very similar to a 4.0, regardless of the on paper claims, and the price of the Tamora family wasn't a great deal less than the Tuscan.
You could also hypothesize that it was a reflex reaction to the 4.0 reliability problems, returning to a capacity closer to the original 3.5 litre Speed 6 design.
Cheers,
Pete
The 3.6 gave them a more "entry level" 350bhp engine to go into the new lower-cost Tamora family replacing the Chimaera. Of course that's largely just marketing, since as you say the real world performance is very similar to a 4.0, regardless of the on paper claims, and the price of the Tamora family wasn't a great deal less than the Tuscan.
You could also hypothesize that it was a reflex reaction to the 4.0 reliability problems, returning to a capacity closer to the original 3.5 litre Speed 6 design.
Cheers,
Pete
davemac250 said:
Does that mean that the 3.6 is regarded as more reliable then?
Hard to say. They are mostly 2003 onwards, so perhaps no more reliable than the 2003-on 4 litres, but later engines are certainly more reliable than 2000/2001 versions. People argue that the shorter stroke means less reciprocating mass, but I can't see that affecting top end reliability, which is what causes the majority of rebuilds.Pete
Thanks,
But................
Can you explain how having the power further up the rev range gives the valve train an easier time?
To me that is counter intuitive.
From my biking past, if I had a 600 and had to scream the nuts off of it to get into the power I expected it to wear vales, seats and guides faster than a 1000 bike ridden at the same pace.
I might be missing something, I usually do!
But................
Can you explain how having the power further up the rev range gives the valve train an easier time?
To me that is counter intuitive.
From my biking past, if I had a 600 and had to scream the nuts off of it to get into the power I expected it to wear vales, seats and guides faster than a 1000 bike ridden at the same pace.
I might be missing something, I usually do!
The nose of the cam where the valve is fully open is where it has the geatest loading from the valve spring . At low rpm opening you are pushing the mass of the valve train and compressing the spring. At high rpm the valve is decellerating as it gets to the nose of the cam decreasing the load on the cam and follower.That is the momentum of the valve , retainer and follower are working against the valve spring taking load of the cam lobe.I hope i have explained this well enough , David
icraigmy said:
S1M VP said:
and as I understand there are not huge differences in performance Vs the 4.0 ... so why did they bother?
I disagree with that statement. I have noticed a hell of a difference in performance with my 4.0L over the original 3.6L.s6boy said:
May get shot down in flames here, but wasn't the Speed 6 originally designed as a 3.6l and then went into production as a 4l.
I do believe that you are right on this point. I also understand that there is a limit to how large these engines can be and that 3.6/4.0/4.3L are the most efficient sizes to have. As a result, I would not consider having a 4.7 conversion. I think the following is correct but no doubt someone from the factory will be along to correct me if I am wrong.
The move from the original 3.6L to 4L was due to the 3.6's power delivery being rather too different to the V8's. The stroke was increased to improve the torque and the early cars were all 4 litres. The Tamora was introduced with a 3.6 as the 3.6's power delivery is dependent on rev's and therefore 'feels' easier to control for the Tamora's target market. Truth is the 3.6 is a rev crazy hooligan so it's all relative.
Some past posters have said they could tell little differenc ebetween the engines,others think the difference is very noticable.You have to factor in build variation,driving style and power delivery prefernces into what you hear.
The move from the original 3.6L to 4L was due to the 3.6's power delivery being rather too different to the V8's. The stroke was increased to improve the torque and the early cars were all 4 litres. The Tamora was introduced with a 3.6 as the 3.6's power delivery is dependent on rev's and therefore 'feels' easier to control for the Tamora's target market. Truth is the 3.6 is a rev crazy hooligan so it's all relative.
Some past posters have said they could tell little differenc ebetween the engines,others think the difference is very noticable.You have to factor in build variation,driving style and power delivery prefernces into what you hear.
OK ... so to summarise
Some ppl have found a difference in power, whereas others have experienced little difference - could be generally down to build variation, but also more likely to be some difference due to capacity increase in 4.0
3.6 seems to be recommended by those who have owned one
OK, thanks guys, if this is the case I don't see too much reason to let the 3.6/4.0 be much of a decision factor, providing it's in the 'right car'
Cheers, P
Some ppl have found a difference in power, whereas others have experienced little difference - could be generally down to build variation, but also more likely to be some difference due to capacity increase in 4.0
3.6 seems to be recommended by those who have owned one
OK, thanks guys, if this is the case I don't see too much reason to let the 3.6/4.0 be much of a decision factor, providing it's in the 'right car'
Cheers, P
s6boy said:
Far Eastender said:
...other stuff... I would not consider having a 4.7 conversion.
I think I remember reading you were having work done Ian how's that going, are you going the full 4.3 route?Gassing Station | Speed Six Engine | Top of Page | What's New | My Stuff